IPAC2013 - List of Authors (Feng, C.)

Paper	Title	Page
TUPEA030	High Brightness and Fully Coherent X-ray Pulses from XFELO Seeded High-gain FEL Schemes	1214
	H.X. Deng, C. Feng SINAP, Shanghai, People's Republic of China
	The successful operation of the hard x-ray self-seeding experiment at the LCLS opens the era of fully coherent hard x-ray free electron lasers (FELs). However, the shot-to-shot radiation fluctuation is still a serious issue. In this paper, high-gain, single-pass x-ray FEL schemes seeded by the narrow bandwidth radiation signal from an x-ray FEL oscillator were proposed and investigated, which are expected to generate high brightness, fully coherent and stable x-ray pulse. A simple model has been developed to figure out the temporal and the spectral structures of the output pulses in x-ray FEL oscillator. And options using two synchronized accelerators and using one accelerator were considered, respectively.

TUPEA033	Proposals for Chirped Pulse Amplification in HGHG and CHG at SDUV-FEL	1217
	C. Feng, L. Shen, D. Wang, D. Xiang, M. Zhang, Z.T. Zhao SINAP, Shanghai, People's Republic of China
	In this paper, a proposal to generate intense ultra-short free-electron laser (FEL) pulses at Shanghai deep ultraviolet FEL (SDUV-FEL) by combining the chirped pulse amplification (CPA) technique with the high-gain harmonic generation (HGHG) technique is presented. In this proposal, a frequency chirped seed pulse obtained by stretching an ultra-short laser pulse is first used to create frequency-chirped bunching at the laser harmonics in an electron beam; then the frequency chirped harmonic radiation is amplified by an energy chirped electron beam; finally the output radiation pulse which inherits the properties of the seed pulse is compressed to provide an ultra-intense ultra-short radiation pulse. The feasibility and performance of this CPA-HGHG scheme are studied with start-to-end simulations using the parameters of the SDUV-FEL.

TUPEA038	Pre-chirp Control Broadband Non-collinear Optical Parametric Amplifier for the Future Laser Weak-field Accelerator	1223
	L. Shen, C. Feng, L. Feng, D. Wang, H.F. Yao, W.Y. Zhang, Z.T. Zhao SINAP, Shanghai, People's Republic of China
	Ultra-short pulse has been proved to be a very useful tool for accelerating electron close to GeV now. But limited by gain narrowing effect, conventional CPA technology is quite hard to get less than 30fs at high energy level. Non-collinear optical parametric amplification (NOPA) looks more and more attractive for generating super-broadbandwidth pulses which is possible to be compressed to ultra-short pulses. Previous NOPAs, pumped by 400nm pulses, were using BBO crystals to reach shorter signal pulse durations. But the associated spectral bandwidths are still strongly linked with higher order nonlinear effects. which make it quite difficult to get higher energy with short pulse duration. Here we proposed to use pre-chirped few nm bandwidths around 515nm pumped pulses to amplify ultra-short pulses centered at 800nm. In our setup, we have found just one dramatical geometry configuration which support that we have possibility to get amplification from 720nm to 900nm, which will support to less than 10fs by well re-compression. This design is well adapted for BBO crystals. But the idea could be used also for other crystals.

Paper

Title

Page

High Brightness and Fully Coherent X-ray Pulses from XFELO Seeded High-gain FEL Schemes

1214

H.X. Deng, C. Feng
SINAP, Shanghai, People's Republic of China

The successful operation of the hard x-ray self-seeding experiment at the LCLS opens the era of fully coherent hard x-ray free electron lasers (FELs). However, the shot-to-shot radiation fluctuation is still a serious issue. In this paper, high-gain, single-pass x-ray FEL schemes seeded by the narrow bandwidth radiation signal from an x-ray FEL oscillator were proposed and investigated, which are expected to generate high brightness, fully coherent and stable x-ray pulse. A simple model has been developed to figure out the temporal and the spectral structures of the output pulses in x-ray FEL oscillator. And options using two synchronized accelerators and using one accelerator were considered, respectively.

TUPEA033

Proposals for Chirped Pulse Amplification in HGHG and CHG at SDUV-FEL

1217

C. Feng, L. Shen, D. Wang, D. Xiang, M. Zhang, Z.T. Zhao
SINAP, Shanghai, People's Republic of China

In this paper, a proposal to generate intense ultra-short free-electron laser (FEL) pulses at Shanghai deep ultraviolet FEL (SDUV-FEL) by combining the chirped pulse amplification (CPA) technique with the high-gain harmonic generation (HGHG) technique is presented. In this proposal, a frequency chirped seed pulse obtained by stretching an ultra-short laser pulse is first used to create frequency-chirped bunching at the laser harmonics in an electron beam; then the frequency chirped harmonic radiation is amplified by an energy chirped electron beam; finally the output radiation pulse which inherits the properties of the seed pulse is compressed to provide an ultra-intense ultra-short radiation pulse. The feasibility and performance of this CPA-HGHG scheme are studied with start-to-end simulations using the parameters of the SDUV-FEL.

TUPEA038

Pre-chirp Control Broadband Non-collinear Optical Parametric Amplifier for the Future Laser Weak-field Accelerator

1223

L. Shen, C. Feng, L. Feng, D. Wang, H.F. Yao, W.Y. Zhang, Z.T. Zhao
SINAP, Shanghai, People's Republic of China

Ultra-short pulse has been proved to be a very useful tool for accelerating electron close to GeV now. But limited by gain narrowing effect, conventional CPA technology is quite hard to get less than 30fs at high energy level. Non-collinear optical parametric amplification (NOPA) looks more and more attractive for generating super-broadbandwidth pulses which is possible to be compressed to ultra-short pulses. Previous NOPAs, pumped by 400nm pulses, were using BBO crystals to reach shorter signal pulse durations. But the associated spectral bandwidths are still strongly linked with higher order nonlinear effects. which make it quite difficult to get higher energy with short pulse duration. Here we proposed to use pre-chirped few nm bandwidths around 515nm pumped pulses to amplify ultra-short pulses centered at 800nm. In our setup, we have found just one dramatical geometry configuration which support that we have possibility to get amplification from 720nm to 900nm, which will support to less than 10fs by well re-compression. This design is well adapted for BBO crystals. But the idea could be used also for other crystals.